Adeniji Peter Oluwasegun
Smart Contract Engineer with hands-on experience designing, auditing, and deploying secure EVM-compatible protocols using Foundry and Hardhat. Specialized in multi-signature vault architecture, on-chain governance state machines, ERC-2535 Diamond proxy upgradeability, and Merkle-tree based token distribution systems.
Identified and remediated critical access-control, re-entrancy, and gas-griefing vulnerabilities in production-grade Solidity codebases. Complementary backend engineering experience building Node. js/Type Script microservices with Prisma ORM and third-party API integrations.
Experience
Backend Engineer (Collaborator)
Gridee
Remote
Production Backend Platform — Node. js / Type Script / Prisma / Redis Remote Authored and merged 3 production pull requests (PR #16, #17, #23) into gridee-backend, contributing 1,494 additions across 37 changed files covering tenant authentication, bot registration, and multi-channel inquiry flows. Designed and implemented tenant Controller. ts with Zod-validated REST endpoints for tenant registration, OTP verification via Redis (10-min TTL), and property-code validation against the active database — enabling secure onboarding across Whats App and USSD channels (PR #16: 697 additions, 17 files).
Engineered end-to-end tenant balance and transaction history query flows across both Whats App API and USSD menu interfaces, with template alignment to the project's design system (PR #17: 524 additions, 10 files). Resolved Termii and Blockchain API integration conflicts and fixed a critical "Shell User" registration bug to ensure clean user provisioning (PR #23: 273 additions, 10 files).
Web3 Developer & Open Source Contributor
Independent
Remote
Smart Contract Engineer Remote Design and deploy secure, gas-efficient Solidity smart contracts specializing in Diamond proxies (ERC-2535), multisig vaults, and modular governance protocols using Foundry and Hardhat. Deploy and verify contracts on EVM-compatible chains (Celo Sepolia, Ethereum Sepolia) using Hardhat Ignition and Foundry broadcast scripts.
Conduct manual security reviews: access-control audits, re-entrancy checks, tx. origin phishing analysis, gas-stipend failure identification, and storage-layout validation.
Education
Self-Directed / Specialized Web3 Training
Focused study: EVM internals, Solidity gas optimization, smart contract upgrade patterns (ERC-2535, EIP-1967), EIP-712 signature schemes, Merkle tree verification, and Foundry-based testing and fuzzing.
Skills
SolidityJavaScriptTypeScriptHTML5CSS3SQLFoundryForgeCastAnvilHardhatEthers.jsWagmiViemOpenZeppelin v5Node.jsReact 19Next.jsExpress.jsPrisma ORMERC-2535 (Diamond Proxy)ERC-20EIP-712 (Typed Structured Data Signatures)EIP-1967 (Proxy Storage Slots)Foundry fuzz testingForge coverageSlither static analysis
BLOCKCHAIN & SMART CONTRACT PROJECTS
ARES Protocol
Lead Smart Contract Engineer
Modular Governance & Merkle Reward Distribution Framework (Foundry / Solidity ^0.8.20) Architected a 4-pillar modular governance protocol (ProposalSystem, DelayExecution, SignatureVerifier, MerkleDistributor) with strictly defined interfaces, enabling independent module upgrades and isolated blast-radius containment. Engineered a multi-stage proposal state machine (Proposed → Approval → Queued → Executed) enforcing a mandatory 1-day voting delay and 1-hour execution timelock, creating a 25-hour observability window that mitigates flash-loan governance manipulation.
Implemented economic security barriers: 0.1 ETH proposal bonds with admin slashing on cancellation and 10 ETH per-proposal withdrawal caps to limit blast radius of compromised governance keys. Developed SignatureVerifier.sol using EIP-712 domain-separated structured data signing with on-chain nonce tracking, preventing cross-chain and cross-contract signature replay attacks.
Built MerkleDistributor.sol with gas-efficient bit-packed uint256 claim bitmaps (tracking 256 claims per storage slot), reducing claim verification gas by orders of magnitude compared to mapping(uint256 => bool). Authored comprehensive ARCHITECTURE.md and SECURITY.md threat model documentation covering 5 attack vectors (governance manipulation, treasury drains, proposal griefing, signature replay, double-claiming) with corresponding mitigation strategies.
Secure Eviction Vault
Smart Contract Security Engineer
Security-Hardened Multi-Signature Vault with Merkle Airdrop (Foundry / OpenZeppelin v5) Refactored a monolithic multisig vault into a modular multi-file architecture with 3 interfaces (IMultisig, IAirdrop, IVault) and 5 composable modules (MultisigCore, TimelockExecution, MerkleAirdrop, SignatureUtils, PauseModule). Identified and remediated 5 critical vulnerabilities: restricted setMerkleRoot, emergencyWithdrawAll, pause, and unpause to onlySelf modifier (callable only via multisig executeTransaction flow), eliminating unauthorized admin access paths.
Replaced tx.origin with msg.sender in the receive() fallback to prevent phishing deposit attribution attacks; replaced all .transfer() calls with .call{value: ...}("") to support smart contract wallets (Gnosis Safe, Argent) and avoid 2300 gas stipend failures. Implemented TimelockExecution.sol enforcing a mandatory 1-hour delay between multisig threshold confirmation and execution, following a Submit → Confirm → Timelock → Execute lifecycle.
Integrated SignatureUtils.sol using OpenZeppelin v5 ECDSA and MessageHashUtils for off-chain signature verification within the vault's governance flow. Wrote a comprehensive Foundry test suite (EvictionVault.t.sol) covering deposits, withdrawals, full multisig lifecycle, governed administrative actions, and Merkle airdrop claims.
Foundry-Hardhat Diamonds
Smart Contract Engineer
ERC-2535 Diamond Multi-Facet Proxy with ERC-721 Extension (Hardhat + Foundry) Engineered a hybrid Hardhat/Foundry development environment implementing the ERC-2535 Diamond standard with 4 facets (DiamondCutFacet, DiamondLoupeFacet, OwnershipFacet, ERC721Facet) to bypass the 24KB contract size limit and enable granular per-function upgradeability. Refactored LibDiamond.sol and LibAppStorage.sol to utilize native Solidity custom errors instead of require strings, reducing contract bytecode size and minimizing gas footprint during diamond cut operations.
Created a dynamic facet selector generation pipeline for Solidity-based testing, streamlining the deployment and unit testing of multi-facet upgrade scripts across Hardhat and Foundry toolchains.